CEKEALS ON THE BELLE FOURCHE EXPERIMENT FAEM. 5 



difficulty of eradicating it in cultivated fields. This plant commonly 

 is called gumbo weed in this locality because it is found usually on the 

 more impervious soils of the Pierre clay type. 



CLIMATIC CONDITIONS. 



PRECIPITATION. 



The precipitation at Newell is very similar to that of most of the 

 northern- and western portion of the Great Plains, and especially 

 western North Dakota and South Dakota. Within the Black Plills 

 region the climate is more mild and moist than on the Plains, and 



\5' /o /s eo 



2S 



Fig. 2. — Diagram showing the annual and seasonal precipitation at the Belle Fourche 

 Experiment Farm for the 12-year periorl from 1908 to 1919, inclusive. The solid 

 portion of each bar shows the seasonal precipitation, while the total lengtli of the 

 bar shows the annual precipitation. 



the average annual precipitation ranges from 18 to 22 inches. The 

 Black Hills modify the climate of the immediately surrounding 

 country to a great extent, mainly by increasing the precipitation. 

 This effect extends several miles beyond the outlying foothills. The 

 Belle Fourche Experiment Farm is situated about 25 miles from the 

 foothills and, so far as known, is not influenced to any extent by 

 proximity to the Black Hills. 



The total annual precipitation at Newell varied from 6.64 inches 

 in* 1911 to 21.02 inches in 1915. The average annual precipitation 

 during the 12 years from 1908 to 1919, inclusive, was 14.31 inches. 

 This is believed to be about the normal for the region around Newell. 

 An average of 8.57 inches, or nearly 60 per cent of the total, occurred 

 during the five months from March to July, inclusive. This is ap- 



